Boosting visible-light response for the complete decomposition of volatile organic compounds on the Cu-oxide deposited WO3 photocatalyst by the synergistic effects of TiO2

The degradation of volatile organic compounds (VOCs) by photocatalytic systems is the most practical strategy due to its cost performance, simplicity, and environmental sustainability. To address such issues, the photocatalytic activities of tungsten trioxide (WO3) were developed by the deposition of various cocatalysts. In particular, the Cu-oxide (CuO/Cu2O)-deposited WO3 (Cu-WO3) photocatalyst could efficiently decompose acetic acid and acetaldehyde into CO2 under visible-light irradiation, although it exhibited low activity for the decomposition of benzene, toluene and xylene (BTX). Furthermore, a composite Cu-WO3/TiO2 photocatalytic system, which was fabricated by the simple physical mixing of Cu-WO3 with TiO2, was found to exhibit unprecedented reactivity for the complete decomposition of persistent BTX pollutants into CO2 under visible light irradiation. The synergistic effects of Cu-WO3 and the interfacial surface complex (ISC) formed by tolueneadsorbed TiO2 contribute to the efficient visible light response by excitation up to around 600 nm. The reaction mechanism for the enhancement of photocatalytic activity by the Cu-WO3/TiO2 composite photocatalyst is examined in this study.